Cellular Cellular RespirationRespiration

Conversion of Chemical Energy Conversion of Chemical Energy in organic compounds (foods) to in organic compounds (foods) to

chemical energy of ATP, chemical energy of ATP, usable by cells.usable by cells.

9-3 : Respiration9-3 : Respiration How does glycolysis produce ATP? How is ATP produced in aerobic respiration? Why is fermentation important?

Cellular respiration is the process used by humans and other organisms

to release the energy stored in the food they consume

Cellular respirationCellular respiration

ALL cells break down complex organic

(prokaryotic and eukaryotic) (foods)

compounds into simpler molecules. Cells (catabolism)

use some of the energy that is released in(from C-C)

this process to make ATP. (happens in respiration and fermentation)

Aerobic Cellular RespirationAerobic Cellular Respiration

Aerobic – requires oxygen Anaerobic – does not need oxygen Cellular respiration – occurs in the cell, in

eukaryotic cells it is in the mitochondria. It does not refer to ‘breathing’ although it requires oxygen.

Parts of RespirationParts of Respiration

Glycolysis In cytoplasm, no oxygen

necessary, ALL cells Splits a glucose molecule Generates 2 ATP and 2

pyruvates ( pyruvic acids )

Kreb’s cycle Kreb’s cycle

In matrix of mitochondria, needs mitochondria

does not require oxygen Splits C-C bonds ( in

acetyl ) Generates some ATP,

lots of NADH and FADH2 and CO2 as waste

Electron transport chain (ETC)Electron transport chain (ETC)

On the inner mitochondrial membrane

Electron transport moves e- from carrier to carrier in the membrane

Generates ATP Requires oxygen as the

final e- acceptor Also makes water

fermentationfermentation

If oxygen is missing – ETC can not proceed. This causes a build up in NADH. In order to recycle NADH to NAD+ and run the Kreb’s cycle, cells will use an alternative pathway called fermentation.

Must have correct enzymes. Forms

Lactic acid fermentation ( muscles – lactic acid) Alcoholic fermentation (yeast and bacteria – alcohol)

EnergyEnergy

All cells need/ use ATP ATP is adenosine tri phosphate and stores

energy in high energy phosphate bonds 1 kilocalorie = 1000 calories Glycolysis alone is only 3.5% efficient Complete oxidation is 66% efficient Car engines are around 25% efficient Cell work generates lots of heat

S u m m a r yS u m m a r y

C6H12O6 + 6O2 6CO2 + 6H20 + energy

C(H2O)n

“food is burned” producing “exhaust” and “energy” needs oxygen ATP & heat

Compare and contrastCompare and contrast RespirationRespiration

All eukaryotic All cells do glycolysis Carbs and oxygen IN Water and CO2 OUT Mitochondria Inner membrane and matrix 3 parts ETC is final step; makes ATP Releases energy from C-C Cycle; Krebs, separates C ATP, NADH and FADH2

PhotosynthesisPhotosynthesis Only plant cells ? Algae and ? bacteria Carbs and oxygen OUT Water and CO2 IN Chloroplast Thylakoid membrane and

stroma 2 parts Light reaction has ETC and

makes ATP Stores light energy as C-C Cycle; Calvin, connects C NADPH

Key Vocab WordsKey Vocab Words

Glycolysis Aerobic Anaerobic Kreb’s cycle Fermentation Lactic acid ADP NADH FADH Pyruvate

ETC Mitochondria Inner mitochondrial matrix Protein channel Enzyme ATP synthase Diffusion Eukaryote ( eukaryotic cells) Prokaryote (prokaryotic cell)